Performance assessment of a storm water system in an estuarine area – Dafundo case study

Abstract

Performance assessment is an important management tool in the water sector, and its integration on storm water systems’ management is recognised to benefit storm water utilities. A performance assessment framework for urban storm water systems has been developed, comprising objectives, assessment criteria, and performance indicators. The objective of the present work is to test and demonstrate the applicability of the framework as part of the internal validation process. The framework components are evaluated in terms of their definition, relevance, and feasibility, in conjunction with their application to a case study, in an estuarine area served by conventional storm water systems, by developing a performance assessment system. The identified performance failures were related to flooding occurrences, illicit domestic connections to storm water pipes, insufficient hydraulic capacity, and lack of self-cleaning capacity. Different intervention solutions were studied based on the infrastructure asset management planning AWARE-P software. Suggestions to improve the system’s performance and to obtain data for non- calculated performance indicators were proposed.